This invention relates to easy opening cans and, more specifically, to an improved easy opening container wall including inseparable tear strips, each defined by a separate score line, wherein the tear strips may be opened with a single retained tab member, and wherein protective means are incorporated in order to reduce the incidence of laceration.
The ready acceptance of easy opening containers has resulted in extended use of this type of container for a substantial number of canned products, especially beverages such as beer, soft drinks and the like, as well as other products which are non-carbonated. This type of container is characterized by a lever or tab permanently joined to a tear strip, the latter normally bein separable from the can top to provide a pouring spout, in the case of beverages. In the form heretofore used, the tab or top is ruptured along a continuous score line and the pull tab and tear strip is normally removed and discarded.
The convenience of easy opening cans has created problems because of the unfortunate and indiscriminate disposal of the severed portion of the can top. For example, beach and picnic areas have had an accumulation of litter in the form of tabs and tear strips which have been removed from easy opening cans. These discarded tabs and tear strips are quite difficult to clean up because they are small and thus pass through the tines of a rake. Being made normally of aluminum, they cannot be collected by magnetic means. Nonetheless, this type of can is widely used and it is definitely advantageous to provide a solution to the problem of littering while still providing to the public the convenience of easy opening containers.
The numerous advantages incident to the use of easy opening cans are significantly enhanced if a container end is provided including an inseparable tear strip and which is relatively safe to use in the sense that the incidence of lacerations are reduced. As will be appreciated, where a tear strip is not separable from the end wall, precautions must be taken to prevent laceration by the retained tear strip or by the exposed edge of metal formed upon opening of the container. This is particularly true with respect to small children who exhibit a tendency to place their fingers down into the pour opening of an easy opening container.
The packaging industry is generally aware of the problem of indiscriminate littering of separable tabs and tear strips as well as the potential problem of laceration.
Accordingly, it is definitely advantageous to provide an easy opening end wall structure with a retained tear strip system in that there are no detachable components which may be thrown away as litter. In such an end structure, it is desirable to retain, to the extent possible, the opening action, which is in the form of lifting to bring about rupture of the score lines, since the public is accustomed to this type of opening action in an easy opening end wall.
It is also advantageous to provide an easy opening end structure having the advantages previously noted that is a conversion and interchangeable with present tooling used by the industry in the sense that the basic container dimensions need not be altered in order to accommodate the improved end. An additional factor is that the end should provide normal performance for the variety of products packaged in convenient easy opening end type containers, for example, an end structure which is capable of withstanding the normal pressures utilized in the beer and beverage industry, and particularly those products packaged under pressure or which develop pressure during their packaging, for example, pasteurization of certain beer type products.